Introduction:

A hip replacement operation is one of the most successful operations in Orthopaedic Surgery. Hundreds of thousands of these operations are now carried out every year worldwide with excellent results. It’s modern form was invented here in the U.K. in the 1960s by Sir John Charnley.

Hip replacement surgery becomes necessary when the hip joint has been badly damaged from any cause and the resulting pain cannot be satisfactorily controlled by nonsurgical means. The usual problems that can end up in the need for a hip replacement include any one of the many types of arthritis, malformation of the hip since birth or abnormal development and damage from injury.

Non-operative treatment:

The artificial hip operation is one of the options that you have in trying to control the pain of a damaged hip. It is not a life saving operation and hence every patient should carefully consider the alternatives to the surgery in discussion with their GP.Various means can be utilised to try and control the hip pain of bad arthritis. Your GP or Rheumatologist may suggest:

Losing some weight if your are overweight. This is because losing weight will reduce the stresses on your diseased hip and may reduce the pain.

It is often helpful to use a walking stick in the hand opposite to the side of the painful hip as that can reduce the pain by lowering the forces on the bad hip.

Taking pain killers and anti-inflammatory medications.

Advantages:

The damage to the hip joint from arthritis is is usually relentless and in most cases, irreversible. The arthritis wears away an increasing amount of the shiny white gristle (articular cartilage) lining the ball and socket shaped bones that make up the hip joint. It is this cartilage which normally makes the bone ends slippery and helps the joint to move smoothly without friction and also functions as a shock absorber. With time, an increasing proportion of the bone end gets exposed until finally a situation comes where bone is rubbing against bone.

While the patient starts feeling some pain soon after the onset of the arthritis, it is only in the later stages that it gets worse and may become quite restricting. The patient may find that his or her mobility is reduced and even day to day jobs such as walking to the local shops, going up and down stairs and getting up from a chair become painful. In the final stages the hip may cause pain at night in bed and keep the patient from sleeping.

The hip replacement operation is one of the most reliable operations in orthopaedic surgery and consistently reduces or eliminates the pain of the arthritis in most patients. The pain of the operation itself improves very much within the first ten days and is almost gone by 2 to 3 weeks. The artificial hip can also improve the movements in a hip joint that has become stiff from arthritis and permit the patient to resume gentle activity and leisure pastimes. In this manner, it can improve the mobility, independence and the quality of life of most people with disabling hip arthritis. The patients can then get greater exercise and this can help in a strengthening of the effected leg and lead to a feeling of well being. Often patients who have arthritis of both hips are so pleased with their first operation that they ask for the second one to be brought forward and done as soon as possible.

What is an artifical hip joint?

Artificial hip joints are broadly of two types; those that require bone cement to anchor it in the human body and those that do not. There are important design differences between the two varieties. Since a hip joint has two components to it – the ball and the socket, it is possible to have a third type of artificial hip that uses cement on the ball side and none on the socket side. (It is quite unusual to use a cemented socket with an uncemented ball).

The precise choice of implant is made by the specialist taking into account your age, lifestyle, how active you are, whether the hip replacement is being done for the first time or is a replacement for a previously carried out artifical hip and also the specialists own experience and training. Whatever design is chosen, it is very likely to have a bearing made of a metal ball moving inside a plastic cup. While newer implants using other materials such as ceramic are available in the market, Mr. Trakru does not use them as the long term results with these are not as well known as with the other older types.

The socket: The artificial socket is used to replace the natural cup of the hip joint and to house the ball portion of the joint. The type for use with cement is made of a special type of polyethylene which is very tough and slippery particularly when wet. It has ridges on the outside and a wire marker so that its position can be seen on the X-Ray. The ridges are designed to improve the fixation of the cup by the cement. It is implanted into the natural socket by first filling the cavity with the cement and then pushing in the artificial cup which is held still while the cement sets.

The socket for use without cement is made of metal. It has a specially designed surface on its outer side that looks and feels like sandpaper. It is designed to “fool” the body into mistaking it for bone and causing it to join up with the socket much like broken bone heals. However, it is important that the artifical socket is held firmly in place while the healing process is going on and this can take 6-12 weeks. The initial fit is achieved by machining the natural socket accurately and using an artifical socket that is precisely 1-2 mm bigger. The metal socket is then forcibly “jammed” into place and further fixation can be obtained if necessary by using additional screws. The next stage is to place a plastic insert within the metal shell against which the artifical ball will form the joint.

The ball: The ball portion of the artificial hip consists of a metal stem or rod on top of which a metal ball is attached at an angle to mimic the shape of the top end of the human thigh bone. The component for use with cement is fairly smooth on it outer aspect. It is inserted into the thigh bone after first filling the marrow cavity with bone cement and holding it still while the cement sets.

The implant for use without cement has a specially fabricated outer surface as in the case of the uncemented socket. The surface feels porous like a sponge and encourages bone to grow into it. This process takes about 6-12 weeks to complete. It is inserted after first machining the marrow cavity of the thigh bone with special drills and then jamming in a component that is slightly larger.

Hip Resurfacing

The concept of hip resurfacing as opposed to replacing the joint has been attractive to hip surgeons for a long time. The first attempts at doing so were carried out many years before the advent of hip replacement surgery as we know of it now. The main attraction has been the feeling that the procedure attempted to duplicate nature and that only a little amount of bone had to be removed from the hip joint to accomplish the resurfacing. Whereas in hip replacement systems, the whole of the femoral head (the ball of the upper end of the femur or thigh bone) has to be discarded, the resurfacing enables, as the name would suggest, the placement of a new surface onto the femoral head. Only a minimal amount of bone has to be removed from the femoral head -just the amount necessary to reshape the head and machine it to accept accurate seating of the new surface component. Another advantage with the resurfacing procedure is that the ball used in the system is similar to the natural ball and that in turn confers bio-mechanical advantages to the hip. The force transmission is advantageous and the range of movement possible is greater than when a smaller ball is used.

Hip resurfacing was first attempted in a big way in the early 1980s in the United States. Unfortunately, the failure rate was extremely high and the procedure was abandoned within a few years. The technique appeared to be good in theory, but it did not work in practice and there seem to have been a number of reasons for the failures. The most important cause of failure appears to have been the thin layer of UHMWP (the plastic liner) used in the system. Surgeons at that time were forced into using the thin layer of UHMWP because they had to work with only a small disparity between the size of the socket implanted and the size of the femoral head. They had no control on the size of the femoral head or “cap” being used as it had to match the natural size of the femoral head. They could not use a very big socket as that would have meant sacrificing a lot of good bone on the acetabular (natural socket of the pelvis) side. Had they been able to use a large socket, then that would have allowed those surgeons to use a thick UHMWP component.

The surgeons in the 80s were not aware of the particular problems associated with the use of thin UHMWP components. We know now that these thin components are very prone to wear and breakdown. The particles produced during the wearing out process provoke a particular type of reaction from the bone around the hip joint not very dissimilar to the bone “dissolving”. When the bone weakens in this manner it can no longer support the artificial implant which then loosens.

Interest in the concept of resurfacing was reawakened when surgical experience and advances in materials and metallurgy meant that it was possible to produce joint systems that did away with the intervening layer of UHMWP. These newer systems comprised simply of a metal ball articulating with a metal socket. As the metal socket has considerably greater resistance to wear than the polyethylene, there is no difficulty in using the thin metal shells in resurfacing systems. It was apparent that the original concept of resurfacing might work with the newer materials using modern systems and the higher quality finishes obtainable nowadays for metal on metal couplings.

Much of the credit for the renewal of interest in the newer form of hip resurfacing goes to Mr. D. McMinn and Mr. R. Treacy, Orthopaedic Surgeons in Birmingham who have carried out most of the modern research into this system. That probably explains why one of the commonly used resurfacing joints is known as the Birmingham hip.

Hip Resurfacing (further info)

The main features of the hip resurfacing artificial joint are the following:

The system comprises of a metal on metal couple or joint with no UHMWP. The socket is usually implanted without cement while the “cap” or femoral component is implanted with cement.

The shell used on the socket side is quite thin – only 4-6 mm, but this appears to be sufficient.

The “cap” used on the femoral head is virtually the same size as the natural head. In the standard hip replacement operation, the most common used ball sizes are 28 and 32 mm. The larger size may enhance the “feel” of the hip joint for the patient and make it appear more normal than a conventional hip replacement.

Because of the large size of the femoral component, the range of motion achieved is usually (but not always) better than that used with standard hip replacement operations. The larger size also makes this artificial joint more resistant to dislocation than a standard hip replacement and reduces the wear forces per unit area making it in theory, less prone to focal wear.

Most surgeons believe that given the lack of any UHMWP in the resurfacing joint, it is acceptable for patients to be more vigorous and to carry out activities at a higher level than considered wise after standard hip replacement operations. It goes without saying however, that avoiding repetitive impact activity would “strain” the resurfacing the least and therefore minimises the risk of loosening.

There is the potential for the metal on metal resurfacing to outlast by a considerable amount, the usual life expectancy of conventional hip replacement operations. This view is based on theoretical principles and there is no evidence to confirm that is what will happen in practice.

It is possible to convert or revise the resurfacing operation to a conventional hip replacement if that should become necessary in the future. If the “cap” or femoral component fails then, it should be possible to retain the implanted socket component and simply place a standard hip replacement femoral component on the thigh bone side to articulate with the socket of the resurfacing system.

Given that the modern form of resurfacing has only been carried out for about 8 years or so, experience with the system must be considered to be limited. Patients must understand that this is an experimental procedure and theoutcome in the long term is unknown. There have also been issues raised about the generation of tiny metal wear particles as the effect of these particles on health is unknown. This is notwithstanding the fact that NICE (National Institute for Clinical Excellence) has recommended that the hip resurfacing procedure be offered to all patients under the age of 65 needing a hip replacement operation.

As is the case with any surgical procedure, this technique too carries the risk of complications and of things going wrong. There are the usual risks of infection, dislocation, thrombosis and embolism, fracture of the femoral shaft, nerve injury, leg length discrepancy etc. as with the conventional hip replacement. Some patients also report a clunking noise in this hip after surgery with each step and this is probably due to a degree of non congruent movement of the metal bearing surfaces in the early post operative period. The lack of the polyethylene also makes the system more “noisy”. However, as the bearings “bed in”, some of the clunking seems to get better.

There is also one other additional risk with this artificial joint and that is the risk offracture (a break) of the neck of the femur bone – a risk not present with standard hip replacement. The neck of the femur is that portion of the thigh bone that bridges the ball section with the long shaft of the bone. In the standard hip replacement, most of the neck of the femur is removed during the surgery and replaced by the metal implant. In resurfacing however, the whole of the neck portion is retained. The “cap” that is fit on the ball of the femur finishes just where the neck portion starts. There is therefore an area of increased stress at this point. Further, the surgery itself may cause some weakening of the neck of the femur and that can happen either during the operation itself or later, due to interference with blood supply to this area. This combination of factors can result in a fracture of the bone. If there is already some weakening of the neck of femur prior to the surgery, then the risk becomes greater. The weakening before the surgery is a natural consequence of aging through osteoporosis and greater in women and often quite significant after the age of 65 years. Most surgeons do not therefore advise this type of surgery for patients above 65 or those with evidence of osteoporosis on x-ray. There are however, some patients who may be older than 65 years and yet do not have osteoporosis and in those patients, hip resurfacing may be a viable option.

Patients who wish to have this surgery should be aware that, on the rare occasion, it maynot be possible to complete the hip resurfacing procedure even if the surgeon has started the operation. This possibility arises from the lack of flexibility available to the surgeon should the soft tissue tension in the ligaments and muscles around the hip be insufficient to provide stability to the artificial joint. The lack of stability would increase the risk of the dislocation in the replaced joint. If this situation were to arise in a standard hip replacement operation, the surgeon can deal with it by using a longer ball on the femur side. This option is not available to him in the resurfacing system because of the design of this joint. If the only resurfacing size available to him does not do the job, then there may be no option but to convert the operation to a standard hip replacement procedure.

Am I too old?

Your surgeon will need to make an assessment of whether it is reasonably safe for you to undergo the hip replacement operation. The assessment is based primarily upon your physical fitness, your medical history, physical examination and the results of any tests. Age on its own, no matter what, does not preclude surgery.

Seeing a Specialist

In the first instance most patients should make an appointment to see their General Practitioner. The doctor is likely to make an assessment of your hip symptoms and recommend any necessary tests and appropriate pain killers and/or anti inflammatory medications. If the symptoms remain troublesome and do not respond satisfactorily to these treatments, then it is likely that he or she will refer you to see an Orthopaedic Surgeon.

An Orthopaedic Surgeon is a specialist in bone and joint problems and some Orthopaedic Surgeons specialise in Hip and Knee joint replacement surgery. Your GP may refer you to one such if available locally. The length of time that you may have to wait to see an Orthopaedic Surgeon varies across the country but can be up to 8 -10 months in some NHS Hospitals.

At your first appointment with the Specialist, a detailed assessment of your hip problem will be carried out. The Surgeon will examine you and will obtain the appropriate X-rays. He is likely to recommend hip replacement surgery if he finds that your hip has been irreversibly damaged, your pain and other symptoms are not improving with medicines and if you are medically fit to undergo the operation. The Specialist will then explain what is involved in the operation and what the risks and benefits are likely to be. If you agree to go ahead with the operation, then you are likely to be placed on a waiting list. The length of time that patients have to wait on the list for surgery varies from region to region but can be as long as 18 months. If that is the case in your area, you may wish to take up this issue with your GP who may know of Orthopaedic Surgeons with a shorter waiting time and agree to refer you accordingly.

Two weeks before the operation

When it is your turn to have the operation, your hospital will write to you. It is likely that you will be asked to attend a “Pre-assessment Clinic”. This clinic allows a detailed medical assessment to be carried out a week or two prior to the surgery. You should allow a considerable amount of time for this attendance; patients spend about 3 to 4 hours in the hospital. This time is spent in obtaining an in-depth medical history, a general physical examination, various blood tests, a urine test, X-Rays and a heart tracing (ECG). Please remember to bring with you all the medicines that you normally take.

Numerous swabs will be taken at this visit to check for MRSA. The MRSA is a common germ that a lot of us carry on our person and is usually not harmful in healthy individuals. However, it can be quite dangerous in patients who have undergone surgery and infections caused by this germ can be very difficult to treat. Therefore it is good practice to check for the presence of this germ prior to surgery. If the test comes back positive and the germ is present, then you may require a week or two of treatment before the operation can go ahead.

This appointment also presents an opportunity to discuss the operation again with your surgeon and seek answers to any questions that you may have.

Day before the operation:

Most patients are admitted to hospital on the day before the surgery. At that time:

You will be interviewed and assessed by a staff nurse who will show you round the ward.

You will have an identification bracelet fitted to your wrist.

You will also be given and assisted in wearing a pair of surgical stockings. These are very important as they reduce the risk of developing a blood clot in the legs after the surgery.

You may also see the physiotherapist who will be treating you after the operation. He or she may go over the exercises that you will need to do after the operation.

One of the doctors in the team under your specialist will place a identification mark on the leg which is to be operated upon. This is a very important safeguard against inadvertent surgery carried out on the wrong side. None of my patients are allowed to go to the operating theatre without the leg being clearly marked.

You will also be seen by an anaesthetist who will be assessing you to ensure that the anesthesia is safe for you. The doctor will be able to answer your questions about the anaesthesia. He may prescribe some medicine called pre-medication, to reduce your anxiety before the surgery.

A nurse from the operating theatre may also visit you to talk you through the operation.

You will be advised to have nothing to eat or drink for at least 6 hours prior to the surgery.

You may however be allowed to take your tablets with a sip of water, but you should check that with the nurse in charge.

During surgery

In the operation theatre, you will be turned onto your ‘good’ side and supports will be placed front and back to maintain this position during the surgery. The leg to be operated upon will be cleaned with antiseptic and sterile drapes placed around your hip. The surgery is then carried out by the surgeon and one or two assistants. A scrub nurse who handles all the required instruments for the operation is also an essential member of the team. In addition, a circulating nurse is present in theatre to help. Other people who may be present on occasion in my theatre include, trainee nurses, medical and physiotherapy students and visiting surgeons.

The operation takes about 2 hours to perform. When it is finished, a bulky dressing is applied to the wound and a foam wedge (abduction pillow) placed between your legs. The wedge reduces the risk of dislocation (slippage of the ball out of the socket in the hip joint) of the hip. You will then be taken into the Recovery area.

The operation

Once these preparations are complete, you will be transferred to the operating room proper. You will be placed on your side on the operating table and this position will be maintained by means of supports on the front and the back. The whole of the leg will then be cleansed with antiseptic and sterile drapes placed around the hip. Your specialist or a member of the team will then carry out the surgery with the help of one or two assistants.

Incision

A cut about 6-8 inches long is made through the skin on the outer aspect of the hip and upper thigh.

Soft tissue

The fat, muscles and deeper tissues are then carefully separated moving them forwards and backwards to expose the bones of the hip.

Bone work

The hip joint is then dislocated, i.e., the ball of the thigh bone is slipped out from the socket of the pelvis. The natural ball end of the bone is removed. The socket is then prepared for inserting the artificial socket by removing a thin layer of bone. The artificial socket is then implanted in one of two ways. Either your specialist will use bone cement to fix a special plastic socket into the bone of the pelvis or use a metal socket without cement. In the latter case, the socket is held in place by jamming a slightly oversized component into the bone with additional screws if necessary. A plastic liner is then inserted into the metal shell. In both these instances, the bearing surface of the socket is of plastic.

The next step in the operation is to replace the natural worn out ball also called the femoral head, with an artificial one. The femoral head is removed by cutting through with a saw and then the upper end of the thigh bone is shaped to conform to the stem of the artificial ball. A trial implant is then temporarily placed in the femur bone and the function of the hip checked. If all is satisfactory, an exact replica of the trial implant for permanent fixation is then inserted into the thigh bone. Usually bone cement is used to anchor the artificial ball into the thigh but sometimes it may be necessary to use an implant that can be inserted without cement. Once this is completed, the ball is replaced into the socket and that completes the bone work.

Finishing

The soft tissue coverings of the hip joint are then stitched layer by layer. Usually two plastic tubes are placed into the hip joint and brought out through the skin and connected to plastic drainage bottles. Bulky dressings are applied to the wound after which the patient is woken up and transferred to the bed and taken to the Recovery area. Once awake, the patient is taken to the ward.

Will I be put to sleep for the operation?

You will be brought from the ward to the anaesthesia room of the operating theatre in a patient trolley accompanied by a nurse. A member of staff from the theatre will ask you a number of questions from a check list. You will notice that most of these questions enquire about information that you may have already provided previously. The purpose of this checklist is to ensure that no preparations or precautions necessary for the hip replacement surgery have been overlooked. You will then be wheeled into the anaesthesia room. At this time you will have the nurse from the ward with you.

The Anaesthesia room

The Anesthesia room provides a quiet environment for the anaesthetist to work in. You will see your anaesthetist again who may have a junior doctor with him. There will also be another member of staff called the ODA or Operating Department Assistant who is there to help the anaesthetist. All the medicines and tools required to ‘put you to sleep’ for the operation are present in this room. This is where the anaesthetist and his assistants will give you a general anaesthetic.

To start with, three sticky plastic patches will be applied to your chest. These patches are connected to a heart tracing machine (ECG) and will allow the anaesthetist to continuously monitor your heart activity during the surgery. A needle will be inserted into a vein, usually on the forearm so that various drugs can be injected directly into the vein without having to puncture the skin each time. The anaesthetist will place a breathing mask on your face and before long you will find yourself drifting off to sleep. Other monitoring equipment may then be applied. After you have been ‘put-out’, a breathing tube will be inserted into the throat area which will allow oxygen and other gases for the anaesthesia to go to your lungs.

A rubber tube is then inserted into your bladder so that the activity of your kidneys can be checked continuously during the operation. This tube is left in place for at least 24 hours afterwards so that you do not have to worry about emptying your bladder. Once all this has been accomplished you will be wheeled into the operation theatre.

MIS (Minimally Invasive Surgery) Hipreplacement

MIS or minimally invasive surgery is a recent development in the field of hip replacement surgery. It all started about 4 years ago when a couple of surgeons in the US devised a new method of “opening” the natural hip joint through a smaller cut on the skin and with less muscle trauma. The soft tissue damage caused in exposing the natural hip and implanting an artificial replacement was less than in the conventional operation. They found that patients appeared to have less pain after this surgery and were also able to recover the use of the operated leg quicker and therefore left hospital sooner when compared with patients who had undergone a conventional hip replacement..

A lot of development work went into this method of implanting artificial hips. The smaller incision had the disadvantage of making it difficult for the surgeon to visualize the tissues. Special instruments had to be developed to minimise this difficulty. Light conducting fibreoptic cables were used within the incision area to aid visualisation as the light from the overhead lights was sometimes insufficient. The surgeons were able to reduce the length of the incision from the conventional 15 – 25 cm to about 10 cm. With time it became apparent that the length of the skin incision per se was not the main advantage with this technique. Instead it was the reduced trauma or damage to the muscles around the hip that was the key to early functional recovery and the reduced pain with these techniques.

There are very few surgeons who have done large numbers of operations using these techniques. It is apparent from their experience that

These operations are technically more demanding.

There is a learning curve with these operations; i.e., surgeons get better at the operation as they do more.

There is a higher complication rate. The main complication, in addition to the usual ones, appears to be a fracture of the femur bone either during or shortly after surgery. There are also reports of significant numbers of patients reporting numbness on the front of the thigh with some of these techniques. However, the numbness appears to be temporary in the majority and settles spontaneously with time.

Not all patients are suitable for these techniques. At times it may become necessary to convert a MIS approach to a conventional one during the operation.

It is possible for patients to go home in 24-48 hours after the two incision or single anterior incision approach.

There is no scientific evidence at this time of a specific advantage in the long term with the MIS hip over that carried out in the conventional manner.

MIS Hip (further info)

Over time three separate minimally invasive surgery hip-replacement techniques have developed. Each of these are “new” and experience is evolving with their use.

1. The small incision hip.

2. The two incision hip with x-ray control.

3. The single anterior incision hip.

The small incision hip:
This was the first attempt at the MIS hip. The techniques used were much like in the conventional hip replacement operation, but carried out through smaller cuts in the skin and so involved less muscle cutting. With time and experience the skin and muscle cuts used became progressively smaller.

The two incision hip:
About 3 years ago, another new technique of performing the surgery was devised. This involved two incisions and the procedure came to be known as the “Two Incision Hip” . This was a radically different approach. The operation was carried out on a “x-ray friendly” table and required the use of x-rays during the procedure. A 5-6 cm cut was made in the groin area. The muscles were separated to access the hip joint and the artificial socket placed under x-ray visualisation. The use of x-rays was necessary as the surgeon was not able to see the natural socket cavity and had to depend upon x-rays to place the components properly. The femoral component was inserted through a second cut made on the side of the hip and also measured about 5-6 cm. The muscle fibres were then separated to insert an “opener” instrument into the thigh bone (femur) followed by the stem component of the hip joint.

The patient experience after the two incision hip appeared to be better than that achieved with the conventional approach using the smaller incision (the small incision hip). Some younger and fitter patients were able to go up and down stairs with 8-10 hours of the surgery. With experience and as the surgeons became better at the technique, patients were well enough to be discharged from hospital at about 24 hours after the operation. As with any new technique, there was a substantial learning curve for all involved. The time taken for the surgery and the complication rate was higher than with the conventional technique. With time, improvements in both of these aspects have come about.

The single anterior incision:
This is the newest technique of MIS hipreplacement surgery. It was developed in the middle of 2003 by a German doctor. This technique is based on a well known and previously described surgical approach though the originator has made a number of modifications to minimise the muscle damage during hipreplacement surgery. It involves a single anterior incision about 9 or 10 cm long. No muscle cutting is required and the socket and the stem can be implanted without the need for x-rays. A special table is required to permit optimum positioning of the leg to aid exposure. From the patient’s perspective, the outcome appears to be similar as for the two incision hip.

Day of surgery

On the day of the operation you will be taken to the operating theatre on a trolley with a nurse from the ward escorting you. Upon arrival there, a member of staff from the operation theatre will ask you a fairly long list of questions which you may find irksome as you would have already provided the answers previously. However, these questions are a means of double checking that all the safety precautions about your surgery have been taken. The nurse will then escort you to the anaesthesia room where you will be given an anaesthetic (put to sleep) and then transferred to the operating theatre where the surgery will take place.

After the operation you will be cared for in the Recovery area where nurses trained in the care of patients waking up from general anaesthesia will look after you. After you have ‘woken up’ sufficiently, which is usually 2-3 hours later, you will be transported back to your ward. You will be experiencing some discomfort in the hip at this time, but regular painkillers will keep your pain under control. You may also be asked to keep an oxygen mask on your face to help in your recovery from the anesthesia. You will be receiving an intravenous drip through the first night after the operation to make up for the blood lost during the surgery. It may also be necessary to give you a blood transfusion.

About 6 hours or so after the surgery you will be allowed to take some liquids by mouth and if your are not feeling nauseous, you may be given a light meal. The nurses will be keeping a close eye on you and taking frequent checks of your pulse, temperature and blood pressure. They will also remove your surgical stockings for a short period to check your heels for signs of undue pressure. Each evening, starting from the day of the operation, you will receive an injection of a blood thinner called low molecular weight heparin. The injection reduces the risk of forming a blood clot in the veins. You will also receive two injections of antibiotics at about 8 and 16 hours after your operation to reduce the risk of developing an infection in your operated hip.

After surgery:

First day after your operation:

You will be checked by one of the team doctors. A blood test will be taken in the morning and repeated on the next two days. This is to check that any loss of blood or body salts is being made up. You will be encouraged to take more liquids and solids by mouth if you are not feeling sick or nauseous. If you are able to do so, then the intravenous drip will be removed.

The nurses will assist to wash you and the physiotherapist will help you out of bed. At this time you may notice two plastic tubes coming out from the wound dressings which empty into bottles. These are inserted to help remove any excess bleeding after the surgery. You will be encouraged to take a few steps with the aid of a walking frame and take some weight through the operated leg. You will then be sat out of bed in a high chair with your operated leg elevated on a foot stool.

The physiotherapist will also supervise you in carrying out a number of exercises for your legs, arms as well as in breathing exercises. The latter are helpful in removing the extra secretions that may have collected in your lungs during the operation. If the secretions are not removed they can increase the risk of getting a chest infection. He or she will also emphasize the precautions to be taken to avoid dislocating your new hip. The precautions include:

using the foam wedge between your legs while in bed for the first few days

not bending the hip more than a right angle or 90 degrees,

using a raised seat in the toilet,

not lying on your side and

not crossing your legs.

The catheter inserted into your bladder will be removed. The support stockings will be removed for about half an hour once every 6 to 8 hours. You will prescribed a number of medications which include iron to help build up the level of blood in your body, painkillers and laxatives.

Second day:

The plastic tubes draining your wound will be removed by the nurse. This is a simple procedure that may cause a little discomfort, but you will be glad to have one less attachment! It is unlikely that you will require any more pain killing injections though you will still be on tablets. The physiotherapist will help you up and and instruct you on transferring safely from bed to chair and back. She will get you walking a little. You will be instructed in the use of the ‘helping hand’ which is a long stick like device with a grasper at the end that you can use to reach for and pick various items. It is important to use this implement as it enables you to avoid bending your new hip excessively. Your blood tests will be reviewed and you may need to have a blood transfusion depending upon the results.

Third day:

With each passing day the therapist will increase your activity. As your strength and confidence grows, you will graduate from using the frame to using two crutches and then to two sticks. Gradually, you will learn to walk further and eventually also do stairs. Your dressings will be changed and you will undergo an X-Ray of the new hip to check its position.

Fourth day:

You will be encouraged to dress in your own clothes and work towards increasing your independence. Your wound will be regularly dressed until it heals over.

Over the next few days:

You will be seeing the Occupational therapist who will assess your need for equipment that would be helpful for you in hospital and after your discharge such as a raised toilet seat, a helping hand, long handled shoe horn etc. Occasionally, some suggestions may be made to make your home environment safer. These include the installation of grab handles in the bathroom or a bannister by the stair case. The nurse is likely to check with you, your discharge arrangements. If you are assessed as likely to require help at home from the social services, they will be contacted. The precise help you will receive however, is decided by the social workers after a full assessment. About a week or so from your operation you will be able to go home depending upon your progress. You will be asked to continue taking your iron tablets for two weeks after discharge. A district nurse will visit you at home on the 12th day after your surgery to remove the staples used to close your skin wound. You should also take your surgical stockings home with you and wear them until your first follow-up appointment which will be at about six weeks. Until that visit you should be using two sticks.

First few weeks after discharge:

The preoperative level of fitness and functional capacity is, as might be expected, the major determinant of the need for support after surgery. Having said that, the “average” patient should be independently mobile with crutches or sticks by the time they leave hospital after hip replacement surgery and capable of negotiating stairs. Most should be able to get in and out of bed independently with the use of assistive devices such as a leg lifter. All patients are advised to continue with the physiotherapy regimen that they had in the hospital and mobilise “little and often”. The idea is to improve the functional recovery constantly by gradually increasing the mobilisations and the prescribed exercises in a steady manner.

It is understandable that confidence will be low at first upon return to home. This is particularly likely for stairs when it would be helpful for another individual to be present with the patient for the first week. Generally patients are advised to use their TED stockings for about 6 weeks and most will be unable to put these on by themselves even with the use of a stocking or sock aid. Where possible, families may wish to help with the stockings first thing in the morning and these can be then left on until the patient retires to bed at night – always providing there are no circulation or skin issues in the feet or legs. Patients can generally manage toileting independently but may require a raised toilet set for which they should have been assessed prior to discharge from hospital. Appropriate grab handles help, but generally the requirement for these is broadly as prior to the surgery. Patients who have level access to a shower, will be able to manage but will appreciate somebody at hand for assist and confidence for about a week or so until they are able to devise a routine that they can implement independently. Wounds are kept covered at this time with a waterproof dressing until the stitches/clips are removed at about 10-12 days after the surgery. Patients will generally find it difficult to get in and out of a low chair or sofa and so a high chair is helpful. Some chairs can be “lifted’ by blocks for the purpose available in shops selling disability aids.

Fetching and carrying will be difficult while using two crutches/sticks. Some items can be placed in a satchel type bag, but that may not be possible for all food items, such as meals in a plate. Some families or carers may find it helpful to have the patient “setup” for the day, by having most needed items and food and drink, including hot drinks in a flask, nearby.

Patients generally experience a steady improvement in confidence and ability but it is not usually before about 4 weeks that the average patient is feeling confident enough to go out for a walk. They will need to be accompanied for about a week and then should be able to manage unaccompanied depending upon their general state of recovery and their state of fitness prior to the operation.

Precautions after the surgery

The hip replacement that you have had is an artificial joint. You need to look after it so that it gives you many years of trouble free service. It is not a new natural joint and cannot be used as one. The precautions to be taken particularly in the first 6-8 weeks are:

Contact your doctor if you notice in the operated area, any redness, leaking fluid or increasing pain.

Do not bend the hip more than a right angle as this could cause the hip to dislocate or pop out of the joint. This means not bending to take the thigh higher than the horizontal.

Avoid low chairs and toilet seats.

Do not bend down to the floor to pick up objects. Use a helping hand.

Do not force the hip to bend to reach your toes such as to clip your toe nails or put on your stockings. Ask for assistance.

Do not twist the hip.

Do not cross your legs.

Do not lie on your side for the first 6 weeks.

In the longer term, there is a small risk of spread of infection to the hip should you have an infection anywhere else in the body or indeed if you are undegoing an operation, internal examination or even dental work. Remember to inform your doctor and he will consider putting you on antibiotics as preventative measure.

Checkups after surgery

Your first follow-up visit will be at 6 weeks after the surgery. Prior to this a district nurse would have visited you at home to remove the staples from your wound.

At the hospital visit, your hip will be checked and all being well, you will be permitted to give up one stick. You may then walk putting all your weight on the new hip and will no longer need to use your surgical stockings. You can also lie on your side if you should so wish.

If the operation has resulted in a noticeable difference in the lengths of the two legs, then you may need to have the shoe built up on the shorter side. Your next visit to see the specialist is likely to be three months after your first and at yearly intervals thereafter.

Risks of a hip replacement operation

Like with any operation there are significant risks of having a hip replacement operation.

Change in the length of the leg: Some increase in the length of the leg on the side of the hip replacement can occur after the surgery. Usually the increase is small and does not require to be treated. Occasionally, the leg may become longer than the other side by about half to three quarters of an inch. If the patient is aware of the difference and finds it troublesome, then a small raise in the shoe of the unoperated side is all that is necessary.

Thrombosis: This is a technical term for a blood clot. Orthopaedic surgery in general, and hip replacement in particular, carries a recognised risk of producing a blood clot in the veins of the leg. Sometimes the blood clot may form inside the veins of the pelvis. While the clot is not dangerous in itself, it can break off and travel with the blood stream to lodge itself in another blood vessel in the lungs or in another organ. In so doing, it may stop the blood flow to that organ and damage it with serious adverse effects. The risk of such a complication is less than one in a thousand with the precautions that we take. The surgical stockings given to patients for use before and after surgery reduce the chances of developing a blood clot. Research has also shown that encouraging patients to start walking early on after their operation also helps to avoid a blood clot as does the use of blood thinners after surgery. My practice is to have the physiotherapists help the patients start walking on the day after their surgery and to routinely use blood thinning injections during the entire time that patients are in hospital.

Dislocation: The term ‘dislocation’ means the slippage of the ball of the hip joint, out of the socket. The risk of dislocation is generally less than one in a hundred. While the chance of the hip dislocating after replacement surgery is permanent, it is highest soon after the operation and in the first 6 weeks. It is to avoid this complication that patients are advised not to bend their hip more than a right angle. This may occur for example, if they were to sit in a low chair or bend to the floor or reach for their toes. Also, crossing the legs or twisting the hip could cause a dislocation and should be avoided.

Infection: This is one of the more serious complications but is fortunately rare. The precise rate of infection across the U.K. is not known but is likely to be about 2%. In order to reduce the risk of infection, patients are given antibiotics routinely into the vein just prior to the surgery and for two doses after. Scientific studies have shown that antibiotics given in this manner play a significant role in avoiding infection. To learn more about infection after surgery, click here.

Nerve injury: Rarely, the hip replacement surgery can produce an injury to the main nerve of the leg called the sciatic nerve. The risk of such an injury is about 2 or 3 out of a thousand. Such a patient may notice that he or she is unable to pull the ankle and foot upwards or downwards and that the feeling in the skin in the calf or shin area may not be quite normal. He or she may be aware of patches of numbness or pins and needles. In the unfortunate situation when the injury does occur, it usually involves only a portion of the sciatic nerve and is reversible. In other words, a substantial recovery occurs with time in the majority of patients.

Fracture of the thigh bone: The word ‘fracture’ is a technical term for a break in the bone. A fracture of the thigh bone is a rare risk during the operation.

Loosening of the artificial hip: The most common problem with an artificial hip is that it does not last for ever. After some time it does not remain fixed to the bones of the skeleton as well as it was after the surgery. This explains the term ‘loosening’. The problem is more prevalent on the socket side than on the thigh bone side. It is however, uncommon for loosening to occur before 10 years from the surgery. More recent advances in technology and technique of surgery suggest that future results may be better compared with previous ones, but the medical profession will know this for sure only with the passage of time. From the patients perspective, loosening of the hip can result in pain. Often this pain is felt in the groin and is worsened by walking. If the components of the hip are definitely loose on X-Rays then it is likely that your specialist will recommend a ‘redo’ or a revision operation. This is to control the pain and to prevent damage to the bone from the loose hip. At times the hip may loosen without the patient experiencing any symptoms and that is why patients are advised to stay under permanent review and to have X-Rays to check their hips. Occasionally, a specialist may have to advise a revision operation based upon the X-rays alone even though the patient may not be experiencing any symptoms.

More about infections:

Infection after the surgery is of three varieties.

Superficial infection: This involves the coverings of the hip joint without extending into the joint itself. In a patient having a superficial infection, the wound leaks fluid excessively and skin around the surgical cut looks red and inflamed. The patients generally do not feel unwell in themselves. The infection can frequently be treated successfully by antibiotics.

Deep Infection: Infection may also be of the deep type which is more serious as it extends down to the artificial hip joint. A patient developing this complication is likely to feel unwell and have a temperature in addition to having an inflammed red wound which leaks fluid or pus. The hip may be painful and walking may make the pain worse.

With this type of infection your specialist is likely to recommend surgery to wash out and clean the infection and also put you on intravenous antibiotics. Sometimes it is necessary to operate again to clean the infection a second time. The antibiotics will generally be continued for a period of 6 weeks and many infections can be cured successfully in this manner. Ocasionally deep infection may not respond to this treatment and will then require to be treated as a late infection.

Late infection: This is deep infection that develops later than about 12 weeks after the surgery. Usually, this type of infection will not respond to antibiotics and operations to wash out the infection. This is because the germs that cause the infection get into tiny crevices of the artifical hip itself rather than just remaining in the living tissues. As the blood does not flow into the artifical joint, the antibiotics do not reach the germs and are therefore not very effective.

The best chance of curing the infection is by removing the artifical hip completely to wash out the infection and using antibiotics put directly inside the hip joint space and also given intravenously. It is usually necessary to wash out the infection at least twice and continue the antibiotics for 6 weeks. During this time the patient has no hip joint at all but is generally able to get about in a limited manner with the aid of two crutches.

The specialist is likely to carry out serial blood tests the results of which can give him some indication of whether the infection is being cured. At about 8 or 9 weeks after the start of the antibiotics, it will be necessary to put a needle into the hip joint under X-Ray control to remove a sample of fluid. This is examined in the laboratory for any persistent infection and if none is found, that is a good indicator of the infection having been treated successfully.

The specialist will however also take into account the results of the blood tests and his physical assessment of the hip to advise the patient whether the infection has been eliminated. Once the infection has been successfully cleared, the specialist will recommend a waiting period before proceeding to implant a new hip. This can vary from a few weeks to a year. The length of this waiting period depends upon a number of factors including the type of germ that had caused the original infection and the state of the patients health and his or her ability to undergo a further major operation.